Network working group J. Dong
Internet Draft M. Chen
Intended status: Standards Track Huawei Technologies
Expires: January 2011 A. Suryanarayana
Juniper Networks
July 7, 2010
Subcodes for BGP Finite State Machine Errordraft-dong-idr-fsm-subcode-01.txt
Abstract
This document defines several subcodes for BGP Finite State Machine
Error that could provide more information to help network operators
in diagnosing BGP FSM issues and correlating network events.
Status of this Memo
This Internet-Draft is submitted to IETF in full conformance with
the provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-
Drafts.
Internet-Drafts are draft documents valid for a maximum of six
months and may be updated, replaced, or obsoleted by other documents
at any time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt.
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
This Internet-Draft will expire on January 7, 2011.
Copyright Notice
Copyright (c) 2010 IETF Trust and the persons identified as the
document authors. All rights reserved.
Dong, et al. Expires January 7, 2011 [Page 1]

Internet-Draft BGP FSM Error Subcode July 2010
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with
respect to this document. Code Components extracted from this
document must include Simplified BSD License text as described in
Section 4.e of the Trust Legal Provisions and are provided without
warranty as described in the Simplified BSD License.
Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC-2119 [RFC2119].
Table of Contents
1. Introduction..................................................22. Definition of Finite State Machine Error Subcodes.............23. Usage of FSM Error Subcodes...................................34. Security Considerations.......................................35. IANA Considerations...........................................36. Contributors..................................................47. Acknowledgments...............................................48. References....................................................48.1. Normative References.....................................48.2. Informative References...................................4
Authors' Addresses...............................................51. Introduction
This document defines several subcodes for BGP [RFC4271] Finite
State Machine Error that could provide more information to help
network operators in diagnosing BGP FSM issues and correlating
network events. This information is also helpful to developers in
lab situations.
2. Definition of Finite State Machine Error Subcodes
This document defines following subcodes for BGP Finite State
Machine Error:
0 - Unspecific Error
Dong, et al. Expires January 7, 2011 [Page 2]

Internet-Draft BGP FSM Error Subcode July 2010
1 - Receive Unexpected Message in OpenSent State
2 - Receive Unexpected Message in OpenConfirm State
3 - Receive Unexpected Message in Established State
3. Usage of FSM Error Subcodes
If a BGP speaker receives an unexpected message
(KEEPALIVE/UPDATE/ROUTE-REFRESH message) on a session in OpenSent
state, it MUST send to the neighbor a Notification message with the
Error Code Finite State Machine Error and the Error Subcode "Receive
Unexpected Message in OpenSent State". The Data field is a 1-octet
unsigned integer which indicates type of the unexpected message.
If a BGP speaker receives an unexpected message (OPEN/UPDATE/ROUTE-
REFRESH message) on a session in OpenConfirm state, it MUST send to
the neighbor a Notification message with the Error Code Finite State
Machine Error and the Error Subcode "Receive Unexpected Message in
OpenConfirm State". The Data field is a 1-octet unsigned integer
which indicates type of the unexpected message.
If a BGP speaker receives an unexpected message (OPEN message) on a
session in Established state, it MUST send to the neighbor a
Notification message with the Error Code Finite State Machine Error
and the Error Subcode "Receive Unexpected Message in Established
State". The Data field is a 1-octet unsigned integer which indicates
type of the unexpected message.
4. Security Considerations
This document does not change the security properties of BGP.
5. IANA Considerations
IANA is requested to make the following allocations from registries
under its control.
This document defines Error Subcodes 0 - 3 for BGP Finite State
Machine Error.
0 - Unspecific Error
1 - Receive Unexpected Message in OpenSent State
2 - Receive Unexpected Message in OpenConfirm State
Dong, et al. Expires January 7, 2011 [Page 3]